The Intern
by OrigamiArrows
Summary: Adia thought an internship at a little town called Gravity Falls would be perfect. Professor Pines had a good reputation and with a Biology degree and a level head, she'd be ready for anything. She wasn't ready. And when the usual brand of weird for Gravity Falls gets even weirder, Adia will have to tread carefully.
1. Chapter 1

**AN: I love Gravity Falls, and I wanted to write this purely for fun. It has an OC (she won't be shipped with anyone) and I'm going to push this story a little further into the horror genre than the show went. I'll also be infusing just a little bit of Spiderwick into the story to help with that, but nothing major.**

 **Depending on the response this gets, I may try to update regularly, otherwise my other fan fiction is going to get most of my attention. Thank you!**

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Adia flipped through the folder, going over the day's objectives as she climbed the wooden steps. Satisfied she had everything in order, she flicked it shut, tucked it under her arm, and knocked on the front door of the cabin.

There was a thud, a muffled curse, and an "Adia?"

"It's me."

"Come in!"

Adia swung the door open and followed the sound of clanking metal. In the kitchen, she found the Professor, on his back and crammed into the cupboard under the kitchen sink.

She knelt next to him. "What are you doing?"

"Ah, the damn sink was leaking and the pipes are so old they've fused together." He grunted, then there was a bang. "Oh for—Adia could you get the pliers from my toolbox and see if you can hold the drain ring steady? Its by the fridge."

Adia dropped her folder and backpack on the table before shrugging out of her jacket. "Are we still going to the mine shaft today?" She found the toolbox and took the pliers.

"Yes, yes, of course. I'm not planning to do this all day, just get the leaky pipe out."

She nodded and tried to get purchase on the drain ring with the pliers. "Can you push the pipe up a bit I need a better grip—oh good." She angled the pliers and gripped the ring, using both hands. "Ready."

"Okay," Professor Pines said, "turn counterclockwise on three. One, two, three."

Adia braced and twisted. The calcium caked drain held for a moment, before giving way with a pop.

"Finally," Professor Pines said. "I should've just waited for you. I've been at this all morning."

"Need anything else?"

"No, I have it now. Just give me a few minutes and we can go."

"All right," Adia said. She returned the pliers to their box and fished a hair band from her own bag. She pushed her braids back with the hair band and straightened it. She already had her hiking boots on and her head lamp around her neck.

"Okay," Professor Pines emerged from the kitchen, wiping his hands with a towel. "Are you ready?"

"Yes," Adia said, pulling her backpack back on.

In the truck, Professor Pines pulled out of the driveway and onto the gravel road. Adia sat in the passenger seat, elbow propped on the window as she watched the scenery.

"So . . . you really think there might be dwarves?"

The Professor shrugged, eyes on the road. "It's worth checking out. Imagine what they could be like!"

"Yeah," Adia grimaced, "but Jeff isn't exactly a reliable source." The gnome always seemed a little off to Adia, but not in a way she could really describe.

Professor Pines chuckled. "Well, it's Gravity Falls. There's bound to be something."

Adia nodded in agreement. There was likely something there, she just hoped it wasn't as dangerous and annoying as the mantors had been. She grimaced at the memory.

One bumpy ride later, the Professor parked just outside the mine entrance. The road was barely there anymore, the brush having reclaimed most of it. Rusty, crumpled beer cans and broken glass litter the entrance and surrounding area.

Despite the heat of the day, Adia pulled on her jacket, knowing it would be cold in the mine. Once the both of them had all their gear on, they stepped into the darkness.

Adia clicked on her head lamp. "So, what's the plan for first contact?"

"Let me do the talking. If we're lucky they'll be open to communication."

He didn't have to mention what would happen if they were unlucky. After the incident with the unicorns, a first-communication-gone-bad protocol had been established. Professor Pines would handle any violent response with one of his mysterious inventions, and Adia would grab the supplies and sprint back to the truck.

Adia had had told the Professor she agreed to this. But she hadn't told him she fully intended to help him if he need it. And considering how often he . . . miscalculated certain risks, it would happen eventually.

Graffiti marred the walls with profanity, poorly draw pieces of anatomy, and pentagrams before the walls continued beyond Adia's beam of light and vanished into the dark. Long after the light from the entrance had faded, they came upon a boarded up turnoff in the shaft.

Professor Pines slipped the map out of his pocket as Adia reached into her own backpack.

He glanced back at her. "This is the one. Ready?"

Adia handed him the crowbar. "Of course."

The professor chuckled, accepting the tool and getting to work. As the rotting boards fell to the ground, they sent thuds echoing down the tunnel. Somehow, the sound reminded Adia how deep into the earth they were, and in Gravity Falls. She did her best to shrug off the anxiety creeping up on her, and the increasing certainty that something was already with them, just beyond the reach of their lights.

When Adia came to Gravity Falls, she'd been unprepared for the strangeness of it. She'd just gotten a degree in Biology at her town's community college, and needing some work experience, her advisor had pointed her to an opening in Gravity Falls Oregon.

Adia had been skeptical at first, but when her first two choices rejected her, and she'd done some research on Professor Pines, she'd changed her mind. His academic reputation at Backupsmore College had been outstanding and the internship description promised something new every day. So she had been prepared for some surprises. She had not been prepared for the gang of pixies that hijacked her car on her first day.

She had a motorcycle now.

"Thank you, Adia," the Professor said, handing her back the crowbar.

She returned it to her pack and examined the new tunnel. Moisture clung to the walls instead of graffiti, and a layer of dirt and dust indicated it had been abandoned for some time.

Adia took a deep breath, banished the last of her hesitation, and followed Professor Pines.

"Professor, if the entrance was boarded up, how would the dwarves get in and out?"

The professor grinned. "Good question. Perhaps there's another entrance, or maybe they don't need to go to the surface. Remember: these "dwarves" may not fit with our preconceptions of them."

"Right." The pixies certainly hadn't.

Moments later, the tunnel ended and they stepped into a cavern. Dust particles floated through her headlight's beam as she looked up into darkness. Adia looked left and right to find the walls had changed little from tunnel to cavern.

Professor Pines checked the map again and grinned. "Well this isn't on the map, so we're probably in the right place. Let's go this way." He pivoted to the right and followed the wall.

After a few minutes, Adia noticed faint lines etched into the now smooth wall.

She followed the line with her light, eventually aiming up. "Professor," she said, "look at this." Illuminated by her flashlight were lines and lines of what had to be text, occasionally broken by a spiraling diagram or other image.

"Amazing!" The professor exclaimed, his own beam dancing across the etchings. "I don't recognize the language. Perhaps it's the dwarves'? Some of the characters resemble the gnome's writing."

While he'd been speaking, Adia had opened the tripod back and began adjusting the legs and height.

The professor turned to her. "Adia could you— Oh, ahead of me I see."

Adia smirked as she took out the camera and screwed it onto the tripod. She was used to documenting whatever they found. This would take a little while though. She'd have to aim the lights and camera before taking the photo, take some notes on the section and label it, then move and do it all again for the next section of wall.

The camera flashed. Adia inspected the photo before showing it to the professor. The etchings were a good size, the lighting was good, and the image was clear.

"Good," the professor said. "If you don't mind finishing this, I'd like to go on ahead."

"I've got it," Adia said, picking up the tripod and walking it down to the next spot.

"Call me if you need anything," he said, tapping the radio on his hip before setting off into the dark.

Adia glanced up from her work every few minutes to see the beam of his headlamp growing smaller and smaller. After the tenth photo or so, she looked up to see his light gone completely. He must have turned a corner, she reasoned, and returned her attention to the camera.

Every so often, between the flashes of the bulb and the moving of the set, she heard the clatter of rocks. The sound was barely audible, muffled by its echo and distance. In a cavern this large, there were bound to be loose stones shifting somewhere.

Adia picked up the tripod, moved it, set it down, aimed the light, and paused. This section of wall was dominated by a diagram, larger than the others. It was a ring of symbols, some familiar, like a pine tree, glasses, and oddly enough a bag of ice. Inside the ring was a triangle, with a giant eye in its center and what must have been arms and legs.

She frowned, her skin prickling. It was simple, as far as etchings went. But none of the other diagrams had recognizable symbols, and the etchings were obviously old, but showed something as modern as a bag of ice.

Adia took the picture and recorded: largest diagram, depicting bag of ice and other relatively modern symbols.

She was reaching for the tripod when her radio crackled. She took it from her belt, listening to the static sputter. After a few seconds of nothing decipherable, she pressed the button. "Professor, are you trying to call me? I can't hear you. Over."

It crackled. "Adia? No, it's not me. I'm getting some static too. There could be something down here causing interference. Over."

"Okay. Over." As soon as she took her finger off the button, a loud bang sounded in the dark, far to the left of her.

Adia swung her light, but the beam only lit the ground for the next twenty feet, before it dissolved into the dark. She took a deep breath. Whatever it was had been far away and probably just a big rock falling or something. Then it occurred to her, that was the direction the Professor had gone.

She scrambled to press the radio button. "Professor, are you alright? Over."

Static buzzed over the radio as she kept her eyes and light on the direction of the noise. Something clattered.

"Professor?" She tried again.

The reply was a quick whisper. "Radio silence."

Her mouth snapped shut. If the Professor wanted radio silence, that meant he needed to be quiet. She could only think of one reason he'd have to be quiet.

He was hiding.

She lowered the radio slowly, sliding it back into her pocket. When nothing came charging out of the dark, she turned to the camera and tripod to start packing up. If she was over reacting, she'd set back up when the Professor returned. Otherwise, she'd be ready to run.

She unscrewed the camera, put it back in the bag, lowered the tripod and snapped the legs back into place, slid it into the case and threw the strap over her shoulder. Using her foot, she scraped a X into the ground to mark where she'd stopped. When she was done, the silence returned.

She checked her watch, it had only been about a minute. Adia sighed. There were three options. Wait here, go to the truck, or follow the Professor.

Adia groaned and took her knife from her belt, marching toward the unknown. She could wait, but the Professor could be in danger. And standing in the dark alone, waiting for someone or something to find her first, wasn't appealing. She'd rather be the one pursuing the problem, than it hunting her.

She crept along, hand on the wall beside her until she remembered the potentially delicate etchings and pulled her hand back. Beyond her sphere of light, something out in the dark scratched against the stone. She froze.

That had been closer, and hadn't been the taps of stone on stone, but an actual scrape. Adia held her breath, and listened. When nothing else moved, she continued.

The wall on her right vanished. A tunnel, rough and unlike the shaft of the mine lead further into the dark. It was narrow, the ceiling just a foot above her head and the walls only three feet apart.

It was likely the Professor had gone this way. He wouldn't find some mysterious tunnel and _not_ explore it. Adia stared into the darkness just beyond the reach of her headlamp, willing the Professor to step into the light and explain so they could leave.

Something did come into the light, but it wasn't the Professor. A black blur rushed out of the shadows along the ceiling of the tunnel.

Adia shouted and barely had time to flinch before the thing snatched her by the arm and haul her back out of the mouth of the tunnel and off the ground.

She got the impression of wings smacking against her shoulders and head before she fell from its grip and back to the dirt. She scrambled to her hands and knees, trying to look everywhere at once.

But there was nothing but her and the ground and the tunnel. As the adrenaline faded and her mind started piecing what had just happened together, she stared at the tunnel.

"A bat?" she said. It was, she was sure now. It was a giant bat. She stood, her legs still shaky.

Adia jumped as another shape materialized from the dark.

"Adia," the Professor said, "are you alright?"

She grinned, fighting off a hysterical giggle. Now was not the time to be laughing. "I am. Are you alright though? Did you see . . ." She gestured off towards the tunnel.

"I'm just fine. The bats?" the professor grinned. "Yes, I found a few of them actually. They gave me a scare, like yours I think." The professor's hand touched the sleeve of her upper arm, and Adia looked to see three gashes torn in the cloth. But there wasn't a scratch on her skin.

The Professor stepped back and pick up his radio. "They may have caused the disruptions over the radio. Perhaps the echo location of normal bats is present in a more extreme form in this species."

"We could set up a recorder," Adia said. "But that's back at the cabin."

"Yes," the Professor sighed, "we'll have to come back another time."

A bat swooped down from the dark and slammed into the Professor. The man managed a startled yell as claws dug into the back of his jacket and hauled him away.

"Ah! Professor!" Adia ran after them.

The bat wasn't able to get the Professor off the ground, but the man was left trying to knock the thing away as his heels scraped through the dust.

As soon as Adia got close enough, she swung the tripod bag off her shoulder and into the bat. It screeched, letting go and flying off into the dark.

The Professor stumbled as he regained his balance. "Thank you. I—" He cut off as a drone of squeaks and wingbeats rose above them. They looked up.

Above them circled hundreds of the bats, dancing in and out of existence as they entered the beams of their headlights.

"We should run," Adia said, surprised at the calm of her voice.

The professor grabbed her arm and yanked her into a run. "Yes!"

Once Adia had her own momentum the Professor let go. "Follow me!"

Something swiped at Adia's braids. She flailed an arm behind her, but the bat was already gone. A few feet ahead, she saw another one dive at the Professor. He ducked away, cursing.

By the time they got to the tunnel, both of them had several scrapes across their faces and necks. They swerved into the tunnel. The bats followed, fewer in number, but closer by the sound of it.

Adia rounded the corner just behind the Professor, expecting claws to grip her by the neck and drag her back into the tunnels. But the beginnings of sunlight illuminated the walls around them, and the noise of flapping wings gradually disappeared, until they ran out of the mine and into the day.

Adia spun the face the mine shaft, panting. But the entrance was a square of empty blackness, nothing about it different from when they'd arrived.

A soft chuckle behind her grew into a booming laugh. Adia turned to stare at the Professor, caught between incredulity and the desire to join in.

"Sorry," he waved a hand, try to control his laughter. "I shouldn't be laughing. Are you alright?"

Adia snorted. "I'm fine. You?"

"Ah, a few scrapes, but I'll be fine." He straightened, pushing his glasses back into place. "How far along did you get with the photos?"

Adia tilted her head. "I got most of them, I think, but there were a few left. Oh, one of the sections depicted modern stuff, like glasses and a bag of ice."

The Professor's eyebrows rose. "That is strange. I'll have to take a look at that. And come back to finish the records, and get audio recordings . . ." He rubbed his chin.

Adia gave him a blank look before yanking open the truck door and hauling herself in. "You have fun with that."

The Professor started. "You don't want to go?"

The cars window was open, so Adia slammed the car door behind her. "No. Well, probably no. Give me a coffee and a few hours and we'll see."

The Professor smirked. "That's fair. And coffee sounds like a great idea." He hopped into the driver seat and started the car. The truck bounced down the dirt road as Adia stared out the window.

The bats had bothered her, but not enough that she wouldn't go back. If they were quieter, and used their lights less, she'd bet the bats would stay asleep long enough for them to get some photos and set up a recorder.

What really bothered her was that damn mural on the wall. The age of the art didn't line up with what it depicted. And that triangle creature in the center . . . she swore she could still feel that eye on her.

But that was ridiculous. She shoved the unease aside and watched the birch trees fly past.

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 **Thanks for reading! If you liked it, or want more, please leave a review!**


	2. Chapter 2

**AN: Here chapter two! So far this story has gotten a pretty good response. Thank you to everyone who's favorited and followed. And a big thanks to Nina Everblade and AngelPines for your reviews!**

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Adia brought her motorcycle to a stop, gravel crunching under the tires. She sighed and took off her helmet, shaking her braids free. Once she'd propped the bike up on its kick stand, she hung a bracelet around the ignition. The glass beads were covered in salt. In theory, they would ward off any thieving pixies.

Adia tucked her helmet under her arm and approached the cabin. When she got to the door, she paused. A note was taped just above the knob.

 _Adia,_

 _I'm down in the lab today. Just let yourself in._

 _-Professor Pines_

Adia took the note and opened the door. Inside, she threw the note in the trash and set her helmet on the dining room table. She took an envelope from her bag. It had the pictures from their cave exploration, freshly developed.

And after putting on her hairband and a set of safety goggles, she pushed the elevator call button.

When she reached the lab, she spotted the professor, hunched over his desk.

He glanced back at her as she approached. "Good morning, Adia."

"Morning," she said. "I've got the photos from yesterday." She handed him the envelope.

He opened it and flipped through the photos. "These came out nicely. Good work."

"Thank you." Adia looked over his shoulder. Most of the photos came out well, with only a few with distortion or blurring around the corners. The last photo, the one with the etching of a triangle within a circle had come out perfectly.

"Is this the one you mentioned?" the professor tapped the photo.

"Yeah," Adia pointed to the section with the ice bag. "That's what I think it is, right?"

The professor adjusted his glasses. "I think so. I'll take a closer look later." He grinned at her. "This is an amazing find! We'll have to find a way to date the carvings, probably with a sample of the stone. And who carved these? Dwarves?" He grimaced. "Or more likely Jeff was messing with us and some other civilization is responsible. Maybe even humans."

Adia filed the other photos in with her notes, and closed the folder as the professor finished his pondering.

"But that research will have to wait." The professor set the photo down and turned to face her. "Today I'm examining the effects of fairy mushrooms." He pulled a rack of test tubes closer and Adia leaned in to get a better look. There were ten of them, each glowing a different color.

"This is what happens when the mushrooms are exposed to water. I'm not sure what causes the glow, or the difference in color. I need some control mushrooms for further tests. Can you get them?"

Adia took out a notebook from her pocket. "Sure. What kind do you need?"

"Marasmius oreades," the professor said. He rose and crossed the room to his book shelf. "I need you to find some that are not part of a ring, and don't have an odd amount of insects near them. My theory is those ones are unaffected by fairies. And I'll need about ten, if you can find them, from different locations." She scribbled down her notes as he spoke.

He returned and handed her _The Location and Identification of North American Fungi._ She found the page with a picture of Marasmius oreades. It had a long pale stem and a light brown cap, with its edges slightly upturned.

She tore of her note sheet from the pad and used it as a book mark before snapping the book shut. "Do you have a sample bag ready?"

"Right here," he said, handing her a leather shoulder bag. Inside would be glass vials, gloves, forceps, a map of Gravity Falls' forests, a disposable camera, a flashlight, a compass, a flare gun with two flares, and a radio. She also had a pocket knife in her jeans pocket.

"Thank you," Adia said, swinging the bag over her shoulder.

The professor clapped her on the shoulder. "Now, even if you don't find ten, be back before dark."

Adia snorted. "Trust me, I will." She had zero interest in wandering through the forests of Gravity Falls, in the dark with who knew what else. She was sure much nastier things than mantours and pixies wandered between the trees at night.

The professor smiled. "Then good luck."

Adia waved over her shoulder as she headed for the elevator.

The earth squelched under Adia's hiking boot as she stepped through a particularly wet patch of forest. She was looking for large patches of grass and a moist environment, which meant lots of mud.

She'd had decent luck so far, having found four different mushrooms in a little over an hour. And she was pretty sure she could see another patch by the base of a tree just ahead.

She knelt by the tree, and opened her fungi book. She compared the pictures, and the details, and determined it was a match. After pulling on her gloves, she reached for the fungus. The cap squeaked, jerked a few inches to the right, and stilled.

Adia froze, blinking at the thing before slowly retracting her hand. With the same slow movement, and without looking away, she slipped her camera from her bag and snapped a picture. Then she stood, backed away, and moved on.

She wanted no part of that mess right now. For all she knew it could be some kind of lure for a bigger creature, like the light of an angler fish. Later, she'd come back with the professor and some of his inventions.

She stepped out of the grove of pines and into a clearing. The grass reached up to her knees and hissed against her jeans as she walked. When she reached the edge of the clearing, she heard the trickle of a nearby river.

It was just a little way into the trees, about ten feet wide. The water danced over smooth stones coated in moss and ferns grew around the bank. It was too deep for her to see the bottom, but there was a bridge. It was a basic wooden structure, covered in spider webs and more moss. Browned leaves lay scattered across the walkway of it.

She stopped before it, confused. She wasn't on any kind of trail, so it seemed odd for this to be here. But maybe a trail had been here once, the bridge did look old after all. She stepped forward, the sound of her boots on wood just a little too loud.

After a few seconds, she was across. She glanced back, shrugged, and moved on.

About half an hour later, she'd found her last patch of mushrooms. She was setting one into a vial, when there was a bang in her left ear. She jumped, managing to keep hold of the vial, but dropping her forceps. Spinning, she jumped to her feet.

As she rubber her ringing ear, a sound like little bells rose. A tiny figure buzzed up to her, inches from her face. The pixie gave her a sharp grin, black eyes glittering and iridescent green wings a blur.

"Damn it, Bell!" she growled, swatting at him. He dove out of her way easily, perching on a nearby branch. Rolling her eyes, she capped her vial, retrieved her forceps, and slipped everything back into her bag.

She glared at him. He showed up sometimes to annoy her, and she was pretty sure he'd been one of the pixies that stole her car. He spoke, sometimes, but had refused to tell her his name. So she'd named him after Tinkerbell.

Bell pulled something from his skirt pocket and hurled it at her. She ducked away, and it burst with a flash of light and a bang. It wasn't big enough to hurt her, but it was annoying. A fairy's version of fireworks? Maybe she could ask him for one.

She reached into her pocket and found she had some spare change. Pulling out two quarters, she held them up so he could see. "Want to trade me for one of those?"

His eyebrows rose in interest. He considered the quarters, then crossed his arms and shook his head.

"Uhh," she reached into her other pockets. No way was she giving him a lighter, or her pocket knife, but . . . "How about now?" She held up the quarters and a stick of gum. Bell grinned.

There was the chance Bell would take both and fly off, but she was hoping he'd make good on the deal knowing he could make future ones. And she was okay losing fifty cents and gum on the bet.

She held them out in the center of her palm. There was a buzz, and a blur of green and blue, and the payment vanished, replaced by a tiny red seed. It looked a bit like a pomegranate seed, with orange streaks running across it and a hard shell.

Taking out one of her vials, she packaged the seed, made a note about it in her papers, and retrieved her camera. When she took Bell's picture, he was crouched on his branch, tearing a big bite out of his new gum. It would probably take him a while to get through all of it.

Noting the length of the tree's shadows, she checked her wrist watch, and found it was five fifteen. It would take her at least an hour to get back. Which meant she should go.

"See you later, probably," Adia waved to Bell and turned back the way she came. Bell wasn't done with her though, as she could hear him buzzing along behind her. At least he wasn't throwing seeds at her.

She found the river, and followed it north to the bridge. When she turned to step onto it, she was jerked back by the hair.

Adia stopped, and half-turned to see Bell yanking on one of her braids.

"Let go!" She snapped, trying to shoo him away without really hitting him.

He glared, gave another, harder pull and pointed to the river.

The sun had moved since her last visit, and now the shadow of the bridge had shifted to and angle further downstream, instead of directly under it. She squinted at the shore line under the bridge. In the setting sun, she could see the white gleam of bone.

The skulls of deer and smaller animals grinned up from the mud alongside ribs, spines, and other bones.

She took a big step back.

"Okay. Good call, thanks." She told Bell. The Fairy let go of her hair and rolled his eyes.

She pointed to the bones. "What did that?"

Bell flew up and toward the bridge. When he was above it, he dropped one of the seeds. It fell into the space behind and below the bridge, where she couldn't see.

There was a bang, a low growl, and Bell buzzed back to her side.

A shape rose, water cascading off it until it stood as tall as the bridge. It was a hunched over thing, with two long, knobby arms and its back was covered in moss and algae. Its face was dominated by a too-large, grinning mouth, a long crooked nose, and tiny black eyes. It was about the size of the professor's truck.

"What are you doing out here?" It asked, in a voice like wind through trees.

Adia watched one of its hands rest against the bridge casually, before it started moving ever so slightly toward her. Bell hissed at it as she took several quick steps back, and the hand stopped.

"Just . . . hiking," she said, not looking away from the hand, and realizing just how long its arms were.

"Ah," the creature said. Its grin split another few inches to reveal sharp, crooked teeth. "Well, please use this bridge to ease your travels" Its eyes were fixed on her, and in the instant she'd glanced it it's face, she was sure it's hand had moved a few inches closer.

"Thank you," she said, moving further back, "but I'd rather not." She really didn't want to mention she had to cross the river to get home, but she suspected it already knew. Behind her satchel, she slid her hand into her pocket, gripped her pocket knife, and withdrew it. She flicked it open silently.

The creature's smile shrank. "Why so cautious? I will not harm you."

Adia nodded to the bones. "I can see those pretty clearly." Bell snickered somewhere behind her.

The creature's arm shot out, and Adia scrambled back. She slashed at it wildly. Its hand closed inches from her, its nails long and caked in mud, as her knife sliced across its knuckles.

She fell, and pushed herself backwards another few feet, pointing her knife, dripping green, at the monster. The hand retracted, and the creature growled, its lips pulled back into a snarl. It glared at her for a moment, before it's grin returned and it sank soundlessly back into the river. The water closed over it, and a moment later the surface was still.

She had no doubt it was still there.

Adia stood, brushing the leaves off her pants. She had to cross the river, but if she went up or down stream, that thing would follow her. She could walk further back into the woods and out of the river's view before moving, but she didn't know how good that things hearing was, or how fast it could move.

She pulled her radio from her hip and hit the call button. "Professor? Over." As she waited, watching the water, Bell returned. He gave her a smug smirk.

"Yeah, yeah, thanks for the warning," she said.

Her radio crackled. "Adia? What is it? Over."

"I'm in a situation. I'm on the east side of Eagle river, but there's a hostile . . ." she raised an eyebrow at Bell.

"Troll," he squeaked. She grimaced.

"There's a troll in the river, and I can't get passed it. Over."

When the professor replied she could hear drawers opening and supplies banging in the background. "I'm on my way. Give me a basic run of it. Over."

"I'm not sure on height, it was partially submerged, but it could be around eight feet. It's about the size of the truck and has a reach of roughly ten feet. It's carnivorous, intelligent enough to speak, fast and it can plan. I don't think it can leave the river. Over."

"Understood. I'm on my way now." She heard a car door slam. "Move away from the river and send up a flare when I tell you to. Check in every fifteen minutes or if something changes. Over."

"Got it. Over."

She moved uphill until she was a comfortable distance away, and sat down to wait. Bell alighted in a bush beside her. Adia propped her head in her hand and regarded him. "Know how to play tic tac toe?"

"That's cheating," she told Bell flatly.

He'd just enchanted the dirt to change when she wasn't looking. She was sure she'd just drawn an O in the center square, and now it was a X. Bell gave her a shrug as if to say 'prove it.' Before she could chew him out, her watch beeped, marking the next check in time.

She hit the button on the radio. "Hello professor. I'm checking in to say I'm alright. Over."

"Good," came the quick reply. "I should be close to your location now. Go ahead and send up a flare. Over."

"Understood. Over." She stood, took her flare gun and loaded it. She glanced at Bell. "You should probably cover your ears." He narrowed his eyes in suspicion, but complied.

Adia raised the gun over her head, pressing her arm against her ear, using her free hand to cup the other, and pulled the trigger. With a bang, the bright orange flare rocketed into the sky. It reached its maximum height and hung there, burning.

Bell clapped and pointed to the gun.

Adia shoved it into her bag. "No. You absolutely _cannot_ have it." He blew a raspberry at her.

"I see it," the radio buzzed. "I'm not far now. I should be there in a few minutes. Over."

Adia sighed in relief. The sun had set about ten minutes ago, and she'd been doing her best to ignore the growing dark around her.

Looking back at the tic tac toe game, she found a row of three X's and a very innocent looking Bell.

"Whatever," she shrugged, "you win." She took her flashlight and flicked it on, readying herself to head back to the water. On a last instinct, she loaded the flare gun and kept in in hand.

When she saw another light moving through the forest toward her from the other side of the river, she made her way there.

They met at the bridge, each standing ten feet away from it on their respective sides.

"Hello professor," she waved.

He snorted. "Hello, Adia. Now, where is this troll?"

Adia picked up a rock off the ground and threw it into the space beneath the bridge. It hit the water with a splash, and an instant later, the water bubbled.

The troll surfaced much faster than she'd thought it could, its hand slamming across the top of the bridge.

The professor jumped. "Well, I can see the problem." He straightened, his expression turning stony as he raised a gun-like device at the monster. "Alright troll, it's time for you to leave."

The creature grinned at him. "Why would I do that?"

"Because," the professor said, "if you don't, I'll shoot you with this. A high power laser gun."

"You made a laser gun?" Adia asked.

The professor shrugged. "It's a prototype. But a good one."

The troll's dark eye flicked between Adia and the professor, before growling. It sank back into the water, and the ripples stilled.

Adia and the professor crept toward the bridge, until they both stepped onto it. The professor kept his gun up and his eyes on the water.

When they met in the center, the water exploded.

A hand appeared out of the spray, grabbing for the professor. He was ready, aiming his gun and pulling the trigger.

But instead of a laser, the gun popped, and did nothing. The professor barely had time for surprise before the hand was closing around his entire arm.

Adia whipped up her flare gun, aimed straight for the troll's eyes, and fired. A burst of fire hit the troll's face and it howled, releasing the professor to paw at its burns.

The instant he was free, they both ran, their boots pounding against the wood. They didn't stop until the river had vanished from their view and the shrieking cries had died away.

Adia stumbled to a halt, panting as the professor did the same.

When he'd caught his breath, he lightly punched her on the shoulder and grinned. "Nice shooting."

She snorted. "Thanks. Is your arm alright?"

He waved it away. "Yes. It may have some bruising, but it's fine." He pulled his laser gun from his belt and glared at it. "I just wish I knew why this didn't work. I was sure I'd had it this time . . . but I'll be back to the drawing board I suppose."

"I'm sure you'll get it," Adia said. She glanced around, but Bell had left at some point. Instead she saw the black spaces between trees, and the flicker of shadows over the ground. "Can we get back to the car? Before something else shows up."

The professor glanced around too. "Good idea." He headed west, and Adia followed behind.

"Did you find all the samples?" the professor asked over his shoulder.

"Yeah," Adia breathed a laugh, thinking of the troll, moving mushroom, and Bell, "and a few other things. I'll tell you about them when we get back."

They made their way to the car and Adia motorcycle without issue. When they regrouped at the cabin, Adia's first order of business was to get to their Gravity Falls master map. She circled the bridge's location on the map in red and wrote "Troll!" next to it.

* * *

 **AN: Please leave a review! I'd love to hear and predictions, or reactions you may have. Thanks for reading!**


	3. Chapter 3

**AN:** Hey, I'm back! This took longer than I wanted, due to my busy schedule and difficulty writing this chapter. I started over twice before I was happy with the direction of it. Thanks so much to AngelPines for your review of the last chapter. I hope you guys enjoy this one.

* * *

Adia hitched her pack higher on her shoulders and glared at the sunlight filtering between the leaves. It was too hot to be hiking today, but Adia knew the work had to be done. The professor forged the path a few feet ahead of her, glancing down at his compass every once in a while.

They were heading uphill, to get a better view of the town. They had maps, but the professor wanted some photos for a more true to life image. Which meant making the miles long hike through the mountains surrounding the town.

"Now," the professor paused, examining his map, "if I'm correct we should reach the next clearing in a few minutes, right over . . . there." He pointed to their left.

Sure enough, the trees parted to reveal the grassy edge of a cliff. There was plenty of room for them and their equipment, but the drop beyond was a shear ninety degrees.

Adia sighed in relief as a gust of wind surged up from the cliff and blew her hair back. She swung her backpack off and set it down, minding the delicate camera inside. Opening the pack, she retrieved the camera.

As the professor set up the tripod he paused. "We'll have to investigate that cliff at some point."

Adia looked up to see him frowning at the cliffs looming on the opposite side of town. With the way they were split through horizontally, it was rather strange. "Any ideas what caused it?"

The professor shook his head. "I haven't had much time to research that yet. Ready?"

Adia attached the camera to the tripod, aimed it at the town and gave the professor a thumbs up. The professor took three pictures as Adia recorded the time and location in the photo log. Once that was done, Adia sat down and took out her water bottle. The professor did like-wise across from her.

"We're half way done now," he said.

Adia groaned. "Yeah. Still too hot though. Is there a reason we didn't wait until fall?"

The professor grinned. "I've been working on deciphering those cave etchings we found, and I think they reference certain locations around Gravity Falls. Obviously the town wasn't there when the records were made, so I need some photos of the area, not just the town."

Adia perked up. It was nice to know all of this was for a specific purpose. "Have you translated anything yet?"

The professor sighed. "Unfortunately, no. I'm getting bits and pieces, but most of the language is entirely new, but I think some of it is Egyptian based. I'll have to do some research on that before I can get much further."

Adia nodded. "I'm sure you'll get it." The man had become fluent in German after four months for study, after all.

"Speaking of which, I'll need you to pick up a few books from the library on your next trip to the city. I don't have the list on me now, but I'll get it to you before then."

"Sounds good," Adia said. She usually made library stops for the professor to pick up various things. She'd gotten a bit of the reputation with the librarians after checking out books like "Norse Mythology," "The Brothers Grimm," and "Bigfoot: Tales of the Legend." Admittedly, that last book had been a compete bust, but the one on Norse mythology had come in handy.

Adia plucked a daisy from the grass next to her, spinning the bloom. In the dirt beyond the patch of flowers, something caught her eye. It was a dog track, pressed into the mud. They were a bit far from town for people to be walking their dogs here, and it was too big to be a dog track anyway. It was nearly the size of her hand.

Adia leaned closer. "Hey professor, there aren't any wolves in this part of Oregon, right?"

"No, there shouldn't be." The professor said, rising to see what she was looking at.

"Is this a wolf track? It looks kind of big to be a dog."

The professor crouched down next to her and frowned at the print. "I think you're right. Maybe there is a pack around here. It is Gravity Falls after all."

Adia rose. "Mind if I photograph it?" She wanted to compare it to some known wolf tracks later, just to satisfy her curiosity. I'd be nice to see the wolf population come back.

"Go ahead," the professor said. He rose, took the camera off the tripod and handed it to her.

Adia took the camera, returned to the patch, and paused. "Where is it?"

The professor stopped folding up the tripod and blinked at her. "Uh? There?"

Adia scanned the earth. It was clear. The stem of the daisy she picked was right there, and so was the patch of mud, but there wasn't a track there. "Okay. It's gone, or I'm crazy, or something is _weird_." She said weird with the inflection that had come to be known as "The Gravity Falls brand" _weird._

The professor shrugged on his backpack and joined her. "Huh? It _is_ gone." They looked at each other, then at the forest and shrugged.

"I'll note it down," Adia said, already taking out her folder and pen, "and keep an eye out for more, I guess." The professor nodded as she scribbled down her notes and packed up. A moment later, they were off again.

The sun was beginning to set, turning the sky gold. They were ready to spend the night in the forest, knowing the trip would take more than a day. They each had a tent, sleeping bag, food, water, fire starters, and radios. They didn't plan on separating, but it was best to be prepared.

After another half hour of walking, the professor jumped, hitching his foot up and away from the path. Adia thought he'd seen a snake until he regained his balance and pointed down.

"Another one!" He turned to her. "Quick, take your picture."

Adia saw the paw print and scrambled to get her backpack off and get the camera out. Once she had it, she ran over, knelt down and took the picture.

"Did you get it?"

Adia narrowed her eyes at the print. It was still there. "Yep. Should we watch it for a bit?"

The professor checked his wrist watch and nodded. "We have time."

They sat at the edge of the path and watched the print. For ten minutes they remained focused, and then, between one blink and the next, it was gone.

Adia jumped up. "Did you see that!"

"I did," the professor said. They approached the point where the print used to be and Adia snapped another photo.

"Do you know anything about this?" she asked.

The professor adjusted his glasses. "I haven't encountered any phenomenon like this before. Maybe there a new type of canine or lupine around here. We'll have to keep an eye out."

Adia glanced around at the woods, the spaces between the trees shadowed in the twilight. They probably weren't going to find it tonight. The professor must have thought the same, as he followed her gaze. "We should probably make camp for the night, before we lose what left of the daylight."

They set off again, leaving the lost paw print behind.

* * *

"So," Adia snickered, "There I am, in the middle of nowhere, it's midnight, with something outside my tent scratching through my cooler, and I have nothing. My bat's in the car, and I have no idea where my pocket knife is."

The professor gave her a look, the light from the campfire reflecting off his glasses. "You didn't store your food in the bear box?"

Adia sighed. "I know, I know. It was stupid but I forgot." She waved a hand. "Anyway, it doesn't sound big enough to be a bear, so I brace myself and get out of my tent and turn on my flashlight." She snickered. "and there is a _raccoon_ sitting, casually in my cooler, half a sausage sticking out of its mouth as it stares at me. And then the damn thing looks me straight in the eye, reaches up, and closes the lid."

The professor snorted, covering his mouth to keep from spitting out his drink. He took managed to swallow and laughed.

Adia grinned. "So I open the lid back up and shoo it away, but it took all my sausage with it."

"I bet you learned to keep your food locked up though," the professor said.

Adia nodded. "Yep. Defiantly learned that lesson. Especially when I only had a granola bar for breakfast." The raccoon had only stolen her sausage, but she was too wary of the eggs it had sat on to eat them.

"There was one time," the professor said, "when I forgot to lock the kitchen window. I woke up in the middle of the night to this awful racket downstairs. As you could imagine, I was ready for something like a ghost or the undead, but it was . . ." the professor paused, his mouth twisting. "Well, it looked like a tiny naked man . . . thing."

Adia raised an eyebrow.

The professor waved his hands. "That's really what it was! It was about the size of a large cat, and it was clambering around my kitchen like a lizard! It had decimated the fridge and was halfway through the pantry when I got there. I chased it around the house for almost an hour before I finally got it out the door."

Adia grinned. "And I bet you learned to lock the kitchen window?"

"Indeed," the professor said with a grimace.

Adia laughed and took a long drink of her soda, finishing off the bottle. "Alright, I'm exhausted. I'm going to head to bed."

The professor checked his watch. "I should probably do the same."

"Goodnight," Adia said, rising and heading for her tent.

The professor waved. "Goodnight."

In her tent, Adia changed into her pajamas crawled into her sleeping bag. She closed her eyes and listened to the sound of crickets and the wind through the trees. Soon, she was asleep.

* * *

Sleep lay heavy on Adia, but something nudged at the back of her mind, urging her to fight her way to wakefulness. When the last of the daze of sleep fell away, Adia sat up, blinking. She wasn't sure what had woken her, so she stared at the far side of her tent, and listened.

Moonlight cast the shadows of swaying branches against the side of her tent as the leaves rustled in the wind. Crickets chirped and frogs croaked. Then something scuffed the dirt outside.

Adia held her breath, turning her head to follow the sound. It was so faint, sometimes she couldn't hear it for several heartbeats, and when it returned it was behind her. She slipped out of her sleeping bag, silently assuring herself it was just a raccoon or a deer or something. But the smarter part of her reminded her this was Gravity Falls. She reached for her pocket knife and flicked it open with a soft click.

The footfalls stopped.

Adia waited, but after at least five minutes, the silence remained. She debated going back to bed, but she doubted she'd be able to sleep. So she reached for her tent's zipper and whipped the flap open before she could over think it. She stood up in the same motion and took one step out, knife raised and turned to scan the camp.

It was empty. The dimming embers of their campfire lay between her and the professor's darkened tent. The shadows of the trees danced over the ground, but nothing else moved.

For a split second, she thought she saw something scattered across the earth of the camp. Tiny shadows in the dirt, laying in circles around the tents and fire. But she blinked, but couldn't get a clear look in the moonlight.

She retrieved her flashlight from her tent, and when she clicked it on, she saw there was nothing after all. She cast the beam over the surrounding trees, catching a deer in the light. It stared at her with glowing blue eyes before bounding away.

* * *

"So, did anything wake you up last night?" Adia asked when they'd reached their first photo point of the day. It was a steep hill, with just enough of an angle and grass to get a foothold, but it would be a pain to set up the tripod.

The professor raised an eyebrow as he took the tripod from his back. "No. Did something happen?"

Adia reached out to hold the body of the tripod steady while the professor adjusted the legs. "No, not really. I did wake up to something moving around the campsite, but I think it was just a deer."

The professor chuckled. "I suppose that was a bit of a relief."

"Yeah. Still feel kinda weird about it though." She couldn't shake the feeling something was off, even with the morning sun above.

The professor snapped three photos of the town as Adia recorded it in the photo log. When he was done, the professor squinted at the town, then the camera. "You know, we may be the first people up here in quite some time, and the view's nice. How about we take a photo of ourselves?"

Adia grinned. "Sure!"

They angled the camera so that the town would still be the center of the photo with the two of them would be standing to the side. Adia stood in position as the professor adjusted the camera and set the timer. When it was ready, he ran to meet her.

They stood side by side, each gripping the other by the shoulder, and faced the camera. Adia flashed a peace sign, smiling while the professor grinned into the camera and waved. With a flick of the shutter, the picture was taken.

Adia went to collect the camera. "I hope it turns out well." They would have to wait until it was developed to see if there was any blurring, but if nothing was wrong, it'd be a great photo.

"Did you hear that?" The professor asked.

Adia shut the camera case and froze. The professor stared downhill, his brow creased. The trees around them rustled in the wind, and somewhere behind them a bird sang. Adia didn't hear anything strange.

After almost a minute, in which the professor hadn't moved, Adia spoke. "What did you hear?"

The professor shook his head. "Nothing. I thought I heard a voice, but it must have been my imagination."

"Hmmm," Adia said, scanning the tree line at the bottom of the hill. The trees and bushes were still, and the shadows beyond were still. Adia finished packing up the camera, and soon she and the professor were back on the path.

They'd only gone maybe two hundred feet when the professor paused. "I think I found more of the disappearing tracks."

Adia peered around him to see a set of wolf tracks. They ran directly across the path, heading from left to right and into the forest.

"I don't think I need another photo, do you?" Adia asked.

The professor shook his head. "If we knew how long it had been here, then yes, but it's not very useful otherwise."

Adia straightened, stepping over the tracks to continue on.

"Hello?"

Both Adia and the professor froze, staring in the direction of the voice. It had been faint, but definitely a woman's voice coming from the right. Adia stared into the labyrinth of trees. The branches were high here, so she could see fairly far into the trees, where moss, logs, and mushrooms carpeted the forest. But beyond the tree trunks closed in around each other, and the rest was shadows. Nothing moved, and Adia realized she couldn't hear any birds or insects. She wasn't sure when they'd gone quiet.

Adia met the professor's gaze. He met her with a serious expression and pointed down. The tracks were gone, but she understood the connection.

"I need help," the woman said. Adia thought she sounded closer now, just beyond where the trees got too dense to see through.

Adia gave the professor an exasperated look. She knew, that he knew, that even though this was very likely not a woman, they had to check now.

The professor flashed her a small smile before his serious expression returned and he mouthed: "stay here," and pointed to the path.

Adia tapped her radio, flicked opened her pocket knife, and gave him a thumbs up. She hoped he got the message of "radio me for back up," but she wasn't sure.

The professor gave her a mock salute, drew his questionable laser gun, and started off the path, stepping over piles of dried leaves and twigs.

Adia watched him progress into the trees, until he vanished between the trunks. Even then, she watched the spot where he'd disappeared. Beside the wind through the trees, it was quiet. The woman didn't call out again, and neither did the professor.

As the tension left her shoulders, simply because she'd been there for so long and nothing had happened, something moved in the corner of her vision.

She turned to look, and time locked into place.

A wolf, as black as ink and much bigger than any dog or wolf she'd ever seen, crouched low feet from her. Its muzzle was pulled back into a snarl, revealing vicious canines.

Then time crashed back into motion and the wolf kicked off from the earth and lunged for her. Adia had a fraction of a second to raise her pack between her and the wolf before it hit her.

Her back slammed into the dirt and a huge paw dug into her shoulder. It pinned her to the ground and its claws dug into sleeve and skin, trapping her knife hand.

She'd hit her head on the landing, but kept her pack up as she shook away her disorientation. The pack was between her face and the wolf, so she couldn't see it, but the pack jerked wildly in her grip as the wolf snarled.

It was a struggle to hang on, and as soon as the wolf ripped it away there would be nothing between her and its fangs.

"Get off!" She yelled, putting as much power into the words she could. She twisted, trying to free her arm that held her knife. She caught sight of its back leg, and gave it a hard kick.

The wolf lost it balance for just a moment, but it had to take pressure off her shoulder to right itself. She wrenched her arm free, registering the feel of its claws raking across her skin, but no pain yet, and slashed at its leg.

It yelped and leapt off her. It darted around the pack, trying to attack her from the back.

She hurled the backpack at it, papers and supplies flying out of the hole torn into the fabric, as she scrambled to her feet. Clutching her knife, she lowered her weight and faced the wolf. "Shit."

The wolf faced her, pacing circles around her. She turned with it, keeping her knife pointed at it. It was wary of the blade now as blood ran down its front leg and left bloody paw prints.

She was bleeding as well, and though she didn't dare take her eyes off the wolf to check, she could feel the sticky hot drip of it down her arm to her wrist.

She knew how this would go. It was afraid of the knife now, but it would either decide to leave, or jump her. If it came at her, she would have one very slim chance for a good stab, and if that didn't work, it was over.

"Don't suppose you'll just leave, right?" she asked it.

Its lips pulled back in a strange bend, and it laughed. A woman's laugh.

The wave of horror that rushed over her almost caused her to miss a step. "Well shit," Adia muttered.

"Put down the knife," the wolf said. "It will be faster that way."

Adia shook her head and rolled her wrist. "Nope. You come over here, I'm taking an eye at least."

It laughed again.

Adia reached for her belt and gripped the radio. "There a wolf here and it's after me. It talks by the way. Over."

The response was instant, accompanied by the sound of crashing brush in the background. "I heard you yell. I'm nearly there. Over."

As they circled each other, Adia had come to face the direction the professor had gone. She glanced up to the trees to see him sprinting toward them.

The wolf glanced over its shoulder and snarled.

The professor leapt onto the path, his laser gun already raised to point at the wolf. As the wolf turned to face him, he pulled the trigger.

There was a buzz, a burst of light that shot five feet to the left of where the gun was aimed, and then a burst of sparks. The gun whirred and died.

The professor's eyebrows flew up in surprise as he dropped the gun. The wolf lunged. Its fangs were only a foot from the professor neck when he threw his arms up. The wolf's jaws locked around his arm and jerked the professor to the ground.

Adia flew at the wolf. It was only a second before she got there, but the wolf shook the professor's arm like a dog would a toy. Adia drove her knife into the creature's back, once, twice, and pulled back for the third when it let go.

It spun and swiped at her with its claws, but she jumped away. Then it blazed past her and into the trees.

"Well," the professor said in a tight voice. Adia turned to see him sitting on the ground, staring at his bleeding arm. His sleeve was ripped away entirely, and the skin beneath was a dripping red mess.

Adia scooped the first aid kit off the ground where it had fallen when she threw her pack, and ran to him. "Okay," she said, surprised at the calm in her voice, "raise your arm. I'm going to wrap it, and you're going to keep an eye out for the wolf. Good?"

"Yes," the professor said, raising his arm and looking a bit pale. "That's a plan. A good plan."

Adia popped open the kit and snatched out the bandages. She began wrapping the wound as tightly and quickly as she could, glancing over her shoulder as she did. The professor was on lookout, but she would bet he was in shock.

When she was done, she looked over the bandages. They were already stained red, but none of the blood was dripping out, so it was probably okay.

"Are you alright?" the professor asked as he lowered his arm, his color returned a bit and his eyes clearer.

Adia glanced at her shoulder. Four gashes tore through her shoulder, but the blood was already dried, and nothing compared to the professor's wound. "I'm okay. But we need to get you to a hospital."

The professor tried a smile, but it was weak. "Ah, it'll take more than this to slow me down. But I agree. If we head . . ." he raised his good hand to point and narrowed his eyes at the forest, "that way, we should get to town within an hour."

"Good," Adia glanced around and held out a hand. "can you walk?"

The professor snorted and took her hand. She hauled him to his feet. He looked down at his shirt with a grimace. "Well, this is ruined."

Adia blinked at him. "It's almost a comfort that that's what you're worried about. _Almost."_ She shook her head and went about recovering the camera back and photo log. With her pack shredded, that was all she could carry. The rest could be replaced later.

The professor collected his laser gun, tucking it into his belt with a sigh and took out his own pocket knife. They stepped off the path, heading north.

"I'll watch the west and front if you watch the east and rear," the professor said, taking front position.

Adia nodded and began scanning the forest as they went looking from right to behind. They found wolf tracks as they went, but kept moving.

"So it can talk?" the professor asked, still scanning his area.

"Yeah," Adia said. "It sounds like a woman. And it's not just a mimic, it was responding to what I said."

The professor grimaced. "That call for help earlier was probably it trying to separate us then."

Adia nodded. It may have recognized the professor as the bigger threat, with his gun, and tried to lure him away to get rid of Adia, then go after him. Once they had regrouped, they were probably a bigger threat than it wanted to deal with.

As they traveled, brush rustled just out of view as a woman laughed, and twigs snapped behind trees. At one point, they heard a baby crying off to the right. The professor and Adia glanced at each other with grimaces, but kept going.

They must have been near the edge of the forest when the black figure of the wolf appeared between the pines, bounding toward them.

"Right!" Adia yelled, pointing her knife.

The professor spun, reaching into his jacket. He pulled out a can of bear spray. Adia took a step back as the professor flicked the tab open.

When the wolf was a few feet away, the professor pressed the tab. Red mist sprayed from the can, directly into the wolf's eyes.

It back pedaled with a yelp, pawing at its eyes and drooling. It flashed them one last snarl before running back the way they'd come.

"Where can I get one of those?" Adia asked, staring at the can.

The professor pocketed the spray. "They're 1.59 at Dusk 2 Dawn."

They jogged the rest of the way, reaching the outskirts of town in minutes. They exited the tree line and found themselves on a residential street. Panting, they stopped in the middle of the street to catch their breath.

"How's your arm?" Adia asked.

The professor lifted the bandaged limb. It was dripping blood again, not a lot, but it was a steady bleed.

Before the professor could answer a van turned the corner, slowing as it neared them. It rolled to a halt and Suzan stepped out.

"My gosh," she gasped. "What happened to you guys?"

"It was a dog attack," the professor said, "could you give us a lift to the hospital?"

"Of course, of course." She opened the van's door. "Hop in."

Adia and the professor clambered in. The backseats were absolutely covered in cat hair, and from the front passenger seat, a scruffy black cat glowered at them.

Suzan shut the door and frowned at her keyring. "Now let's see . . . was it this key? No . . . This key?"

The professor and Adia glanced at each other and sat in awkward silence, waiting for Suzan to remember the right key. Adia questioned the wisdom of letting Suzan drive them, but decided that if Suzan had a car this long, she must be able to drive. Never the less, they both put on their seat belts.

The car rumbled to life. "Ah, yes. Where are we going again?"

"The hospital," Adia said, her voice politely flat.

"Right!" Suzan hit the gas, and with a squeal of tires they were off.

The ride to the hospital would take about fifteen minutes, maybe ten the way Suzan was driving. Suzan flicked on the radio and began humming along to some bubbly song.

"Adia," the professor said, his expression solemn, "I'm sorry for leaving you behind on the path. You could have been killed and it would be my poor judgment that caused it."

Adia was already waving his apology away. "it's fine. And I agreed that you could go check it out and I know there's always a rise here. The wolf could have chosen to go after you instead of me." She knew how badly today could have been for her though. If she hadn't seen the wolf in time to raise her pack, it would have had her by the neck. But she loved the adventure of Gravity Falls, even if there were dangerous days.

The professor nodded. "I think for the future, we should stick together when exploring the unknown. For both our safety. Agreed?"

Adia smiled. "Agreed."

* * *

 **AN:** Thanks for reading! Please leave a review of any thoughts or constructive criticism you may have.


	4. Chapter 4

**AN:** Sorry for the silence everyone, things have been busy. Thank you all for the feedback on this story. The review I've gotten have been wonderful, and helped me write this chapter. Hope it was worth the wait!

* * *

"Happy birthday!" Adia cheered as the professor's front door swung open.

The professor jumped, but relaxed when he registered Adia's words. He smiled, but it was almost a tired kind of smile, as he opened the door for her to step inside. "How did you know it was today?" He glanced from the cake box and wrapped package in her arms to her motorcycle parked outside, raising an eyebrow. "And how did you get those here?"

Adia opened the fridge, grimaced at the mysterious container of bubbling orange goo before moving it out of the way, and set the cake inside. "It was mentioned in your paper about zodiacs, the one you wrote in college, I think." Adia closed the fridge and nodded in the direction of her motorcycle. "And very carefully."

The professor ran a hand down his face. " _That_ paper? That's one of my worst pieces."

Adia shrugged. "I didn't think it was that bad." The paper had been a little vague when discussing the professor's own sign: Gemini, aka the twins, but overall it was decent. She set her package down on the table. "Anyway, present now, or later? I also brought some fireworks I found in my basement, if you're interested."

"Later," the professor said, his tone tighter than Adia had expected, "after we get today's work done."

Adia nodded. She wasn't sure why he sounded so tense. They should just be setting up trail camera's today, which shouldn't be particularly difficult. Was it impolite to get him a cake? Did he not like chocolate? She thought getting him cake would be a nice gesture, but maybe it was overstepping. Well it was the way it was now, and she could be misreading him. Maybe he'd pulled an all-nighter again.

The professor's shoulders relaxed a bit and he opened the hall closet. "I have five trail cameras here, and the approximate locations you should set them up at. Do you remember how to do that?"

"Yeah," Adia said picking one up and looking it over. She just had to put in the batteries, strap it to a tree, and turn on the motion sensor.

Once Adia had the list of locations, the cameras, and her usual expedition pack, she glanced over the house. "What'll you be doing in the mean time?"

The professor sighed. "I'll be here deciphering the cave etchings. I think I'm almost there now, but there are a few key symbols left I haven't figured out yet."

Adia opened the front door and gave him a thumbs up. "Good luck."

The professor waved as he turned to the elevator. "You too."

-o-o-o-o-o-o-o-o-

"Yes, yes, you're very pretty," Adia grumbled as Bell posed in front of a trail camera. "But if I come back and find only pictures of you, I'm getting bug spray."

Bell's shining black eyes narrowed into a glare, but he stopped preening in front of the camera lens.

Satisfied Bell wasn't going to burn through the camera roll, Adia resumed her journey up the trail. A buzz of wings let her know Bell was following.

She'd just gotten to the top of the hill and stopped to admire the view. The forest lay below, extending as far as she could see. A few clouds drifted through the blue sky. A gust of wind rolled over the forest, rocking the trees below like waves.

She looked up, shielding her eyes from the sun to watch a hawk wheeling in the sky. Setting up the trail cams had gone well. She'd half expected a gnome to show up and steal her bag or something, but it had been a peaceful hike.

Just as she was thinking this, her radio crackled.

"Adia? If you're finished with the trail cams, I'd appreciate some assistance. Over."

Adia continued down the hill in the direction of the cabin. "I'm on my way back now. What is it? Over."

"Ah, good. Well that project I had in the fridge is missing, and I can't seem to find it. And everything else in the fridge is gone. Over."

Adia footsteps slowed. What project? There wasn't anything in there capable of movem—did he mean the orange goo? She sighed and ran a hand down her face. Of course he meant the orange goo.

"Right. I'll be there in about ten. Over." She glanced at Bell. "You gonna join me for this?"

Bell grinned. Of course he would be joining the coming chaos.

The trip back to the cabin was quick one, and as it came into view, Adia heard a bang come from inside. She dropped her pack, minding the equipment inside, and ran the rest of the way.

She threw open the door. "Professor!"

"Over here!" There was another bang followed by the sound of something collapsing. Adia snatched up the broom by the door and ran into the living room. She froze in the doorway.

The professor stood, fishing net in hand, glaring at a small . . . thing, scrambling across the wall.

"What is that?" Adia squawked. It looked like a tiny naked man about the size of a raccoon, with beady eyes and sharp teeth. The thing paused, its claws digging into the wall paper and growled at her.

"I don't know!" The professor said, just before he had to duck as the thing hurtled at his head. It flew past him, crashing into a lamp before shoving the lampshade into its mouth and scurrying back up the wall.

The sound of tinkling bells sounded as Bell folded over his stomach laughing.

Adia waved her broom at it in warning as it eyed her. It gurgled at her and dove into an air vent. With a buzz and a flash of light, Bell streaked after it.

The professor frowned at the vent. "Will he be all right?"

Adia snorted. "Better question: will that thing be all right?" She stared at the professor. "I thought you said it was your missing project. The one from the fridge?"

"I thought it had come alive, but I think that thing ate it, actually. It was hiding under the couch when I was looking for the goo." The professor watched the vent for a moment before lowering his fishing net. "The container was broken, the substance was gone, and everything in the fridge had been eaten."

Adia wrinkled her nose. "What was the goo anyway? Didn't you make it?"

The professor looked away. "I ah, found it."

Adia shoulders slumped. "You _found_ it?"

The professor nodded. "In a cave."

Adia stared at him, then threw out her arms. "How did you transport it?"

"Water bottle."

Adia stared at him trying to work out his logic before something occurred to her. "The fridge-!" She tore from the room and into the kitchen. She slipped on some juice spilled in front of the open fridge before sitting up to stare at its shelves. In the center was a crushed and empty cake box.

The professor appeared, looking over her shoulder. "Oh, that too . . . "

Adia sighed. "Sorry it ate your cake." On top of not knowing if she should have brought it, now it had been eaten by some kind of gremlin. The professor offered her a hand up and she accepted.

"So, what do you want to do about your new friend?" Adia asked.

The professor crossed his arms. "Hmm, well, we could try luring it out . . . "

"What if it gets into something in the lab before then?"

The professor eyed the ceiling. "The lab and the house have separate ventilation systems, so we can assume it's safe. For now."

Adia nodded as the professor as he crossed the room to his pantry. He paused in the door frame.

"You don't have anything, do you?" A few weeks into her internship, Adia had realized that the professor regularly forgot to leave his lab and go shopping for food.

"Well—ah, here." The professor leaned in and emerged with a can of beans.

Adia checked the pantry as he left it and found it empty except for a dead spider curled up in the corner. "When was the last time you went shopping?" Adia asked.

"A few days ago," he replied as he opened a drawer.

"Better question: what do you think todays date is?"

"The fifth, right?"

Adia ran a hand down her face. "Professor, it's the _fifteenth_." Sometimes she wondered how this man was a genius.

He grimaced. "Oh. Would you mind picking up a few things for me tomorrow?"

"Not at all," Adia said. Better she did it before he forgot again.

"There's an old raccoon trap in the garage, could you go grab it?" The professor asked, glaring at the can opener, which refused turn properly.

Adia nodded before retrieved her broom and entering the garage. A car with a sheet draped over it took up the far side of the space, with various tool and junk pilled on and around it. A layer of dust covered everything, glowing in the light that streamed through the garage door windows.

Adia scanned the heaps of junk, looking for the boxy cage she'd caught a gnome in once. He hadn't been very happy about it.

She spotted it by the back of the car and knelt to retrieve it. She shook dust and a few panicked spiders from it, and as she did so, knocked it into the open trunk lid. She winced and set the cage aside. She hoped she hadn't scraped the paint.

She pulled away the sheet to check. Adia stared at the rusty trunk lid, unable to distinguish and damage she had caused from the rest to her relief. But something inside the trunk caught her eye. She opened the trunk more and leaned in. Inside was a tire iron, a closed cardboard box, and in the corner, a polaroid.

Adia tilted her head to match its angle and squinted. In it were two teenagers, there arms around each other's shoulders. They stood in front of a school with grins on their faces. They looked familiar. She realized a second later that the one of the right was the professor. The boy had boxy glasses and his hand on the other boy's shoulder had six fingers. She smiled back at the boys. He must have been in high school in the photo.

The boy next to him had a different haircut, and style, but she realized they looked very alike. Too alike to just be friends, or just brothers even. He had to have been the professor's twin.

"Did you find it?" The professor asked.

Adia pulled the sheet back over the trunk. "Yep, here it is." She picked it up. "I bumped it against the car, sorry about that."

The professor waved away the apology. "That things got worse problems than a little ding."

They returned to the kitchen as the professor wrenched the door to the trap open, the spring squeaking in protest.

"Do you have a brother?"

The trap sprang shut on the professor's fingers with a snap. He swore as Adia jumped help free his hand. She pulled the trap door open until the professor could get free. He rubbed his hand and looked at her with a guarded expression.

"Sorry—" Adia started her face red.

"Why do you ask?"

She blinked. "I saw a polaroid of in your trunk. It was you and another boy that looked a lot like you. I was just making sure I hadn't damaged the car, I swear I didn't mean to snoop." Adia felt her regret building, as she realized she might have stumbled upon some personal issues.

The professor sighed and looked at the tiles. "It's fine. That was my twin, Stanley. We . . . lost contact a while ago and I'd rather not discuss it."

"Right. I understand. I won't bring it back up." It explained why he'd seen so tense about the birthday cake. The shared birthday was bound to remind him of his brother and whatever reasons he was gone. Maybe he'd died, or gone down the wrong path. Whatever it was, it wasn't her business. "So, let's try that again?" Adia asked, gesturing to the trap.

"Yes," the professor said, seemingly happy to change the topic. Together they pried open the door and set the trip properly, before setting it down in the kitchen and placing the open can of beans inside.

Adia dragged a chair over to the wall beneath a vent. She climbed up and cupped her hand over her mouth. "Hey, Bell! If you could corral that thing this way, we'd appreciate it!"

She paused and looked over her shoulder to the professor. "You know, I should have made sure he wasn't planning on helping that thing cause chaos." The professor's grimaced matched hers.

"Okay Bell!" she yelled into the vent. "If you help us out, I'll buy you three packs of M&M's." She paused. "The mini ones!"

A moment later there was a flash of blue light at the end of the vent, followed by a bang and the sound of claws on metal. Adia leapt from the chair, scooping her broom off the ground and running for the living room alongside the professor. They dove behind the couch and peaked over the top, watching the kitchen.

"Do you have a camera?" the professor whispered, checking his own pockets.

Without taking her eyes off the kitchen, Adia reached into her pocket and handed him her disposable one.

A moment later, the grate exploded off the vent, and the thing shot across the room in a cloud of blue glitter. It hit the wall with a thwack, its limbs splayed out, before thudding to the floor. It scrambled to its feet and snarled at the vent. Bell watched it from the rim and laughed like tinkling bells before vanishing back into the shaft.

The creature seemed to forget about Bell the moment he disappeared, and sniffed the air. It turned to face the trap.

"Yes," the professor whispered.

It edged closer before seeing the beans and lunging into the trap. It slammed shut instantly.

"Yes!" Adia and the professor cheered, leaving the cover of the couch to approach the trap. The creature snarled at them, the beans forgotten.

The professor snapped a few photos, then paused to raise an eyebrow at the thing. "I have no idea what to name this thing." He glanced at Adia.

She shrugged. "I have no idea."

Their attention was brought back to the creature with a screech of metal. They looked down to see its jaws slam shut on the bars of the cage. It didn't even chew before leaping at them.

The professor ducked it by inches and ran to the other end of the room as it turned its attention on Adia. She yelped, leaping onto a chair as it went for her ankles. It scrambled up the chair. She swatted at it with the broom and leapt away. As she ducked and wove around the kitchen, avoiding the little ankle shredder, the professor went for the door.

"Adia!" he yelled, throwing the door open. "Over here."

Adia ran back in the direction of the door, skidding to a stop a few feet from it and turning to face her opponent. It leapt through the air for her head.

She planted her feet, raised her broom like a bat, and swung it into the little monster with all her might.

The impact sent it out the door in a blur of motion, and the professor slammed the door shut. They both looked at each other, before running to the window. The creature picked itself up, snarled at the house, and scuttled into the forest.

Adia sighed in relief. "Well I'm glad that's done." Then she turned to the kitchen, and saw the fridge door ajar, with broken glass and food smears dripping from it. Stains scattered across the tile and walls. In the living room, the couch and wallpaper were shredded where the creature had run. She groaned.

The professor eyed the mess and ran a hand through his hair. "Why don't you head home, Adia. It's getting late and I don't expect you to clean this up."

Adia gave him and annoyed look. "I'm not leaving you to clean this up by yourself on your birthday." She stared sweeping the glass from the fridge into a pile.

Behind her the professor didn't move for a moment, then he retrieved a mop from the closet and got to work on the tiles.

-o-o-o-o-o-o-o-o-

Adia leaned back against the dining room chair with a sigh. There wasn't much they could do for the couch and wall paper, but the rest mess had been repaired. Now it was time to sit, and enjoy a nice glass of water. All other liquids had been consumed by the little monster.

Bell had left before the sun set, giving her braids a yank before leaving: a reminder to not forget her promise of M&M's. Now it was black out, with the light hanging above the table their only light. Her gaze drifted to the package she'd brought, still on the counter.

"Want to open your present now?" she asked.

The professor glanced at her in surprise. "Oh. I'd forgotten in all the . . ." he waved his arm vaguely at the room. "Of course."

Adia retrieved the package and set it in front of him, before taking her seat and staring at him with a grin. It was the perfect present after all.

The professor gave her an amused smile and opened the box. He paused, his eyes darting over the contents. Then he pulled the gift from the box in a burst of motion. The brand new Dungeons, Dungeons, and More Dungeons box shone in the kitchen light.

"Adia, this is perfect! Thank you." He smiled at the box for another moment, but Adia thought there was something a little sad there. Then it was gone and he met her gaze. "Would you like to play for a while?"

Adia grinned. "As long as it is just a little while. Not the rest of the week."

The professor gave a nervous laugh and opened the box. "I'll be sure to take it in moderation."

They were half way through setting up the board and cards when the professor paused, a smile spreading across his features. "By the way, before that thing tore the house apart, I solved the code."

"The one from the cave?" Adia said, her excitement growing.

"Yes," the professor said, "I haven't translated all of it. But I have the formula to. And I have a name for the deity."

"So, what is it?"

The professor grinned. "Bill Cipher."

Adia thought she should've felt excited. It was an amazing discovery, and would no doubt lead to more. And her excitement had grown, up until that name. It had dimmed, and she found herself uneasy instead of happy. It must have been because it was just Bill. An ancient deity should have had a long, elaborate name. The just Bill part must have been why. That was all. Just vague disapointment.

"That's great," Adia said, shoving the feeling aside. "I can't wait to see what the rest is."

"Me either," the professor said. "But for now, it's your turn." He handed her the dice.

Adia rolled, and minutes later she had entirely forgotten the feeling. They played until morning.

* * *

 **AN:** Thanks for reading! If you have a minute, I always love to hear reviews. They really make my day.


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